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416

COCO-NUT OIL—PALM OIL

For testing for extraneous fats in general, recourse may also be had to
determinations of the critical solubility temperature in absolute alcohol
and in glacial acetic acid and of the melting points of glycerides insoluble
in a mixture of alcohol and ether, as suggested by Grimm.1

*

*  *

Cacao butter is to be regarded as genuine when its physical and chemidal
characters lie within the limits indicated in Table XLV and it does not contain
any of the above-mentioned impurities.

It should be noted that substitutes for cacao butter are sold under various
names, e.g., chocolate butter, consisting of coco-nut oil; cacao butter (coco-nut
oil and Japan wax). The so-called Samana cacao butter is a fat which melts
at about 12° and when left for a long time separates a liquid part; it has D
at 17-5° =0-906, refractonietric reading at 40° = 50-5 and iodine number
= 53-59-

COCO-NUT   OIL

From the albumin or pulp of the coco-nut, fruit of Cocos nucifera. It is
white or pale yellow, and has the consistency of butter and a special odour.
In coco-nut butter well refined for comestible use this odour is almost entirely
lacking, but boiling with a little alcohol and a few drops of cone, sulphuric
acid brings out the odour distinctly.

It dissolves in 2 vols. of absolute alcohol at 30° and in 2 vols. of
90% alcohol at 60°. Its physical and chemical characters are given in
Table XLV.

With Heydenreich's, Hauchecorne's or Brulle's reagent it gives no
sensible coloration, and it does not react with silver nitrate or with furfural
and hydrochloric acid. Characteristic of coco-nut oil are the rather high
saponification number, the low iodine number and the volatile acid number,
which is greater than those of vegetable oils and fats in general.

*

*  *

Pure, edible coco-nut oil is perfectly white (sometimes dyed yellowish to
imitate butter), odourless and neutral or almost so (acidity number not beyond
i% as oleic acid) and has a fresh, pleasant taste.

Industrial coca-nut oil (for soap) is white or faintly yellow and has a more
or less pronounced taste and smell. The finest and whitest quality bears the
name Cochin neige, while the others are called White Cochin, Ceylon and Copra
oils.

The allowable limits for these industrial oils are : acidity (as oleic acid)
up to 4% for Cochin and up to 10% for other qualities ; moisture and foreign
impurities, up to i% ; m.pt. = 20-28°, setting point = 22-14° ', titer (setting
point of the fatty acids) = 16-23° ; volatile acid number = 5-6-8-5 ; saponi-
fication number = 248-260 ; iodine number = 7-68-9-5.

PALM   OIL

From the flesh of the fruit of the oil-palm (Elaeis guineensis and E.
melanococca). It has the consistency of butter, a more or less intense yellow
or orange colour which weakens considerably on exposure to air and light,
and a pleasant smell recalling that of the iris.

1 Chem, Rev. Feft.-Ind., 1914, pp. 47 and 74,ory: [n]n